Hi Roy,
The patch is correct. Looks good. That particular patch signified the 11th Battalion. Horizontal rectangular patch = 1st Australian Division; light blue lower half = 3rd brigade in a division. Brown upper half = third battalion in a brigade. Each patch was different for each battalion.
The shapes of the other divisions were: 2nd Australian Division diamond split horizontally, 3rd Australian Division an oval split horizontally; 4th Australian Division a circle split horizontally, and 5th Australian Division a vertical rectangle split vertically (brigade colour to the rear).
The brigade colours (lower half or rear in 5th Division} were first brigade in the division green, second brigade in the division red, and third brigade in the division light blue. The battalion colours within the brigade from first to fourth were black, purple, brown and white.
There were three exceptions, however, as follows:
4th Australian Brigade (4th Australian Division) horizontal rectangle lower half dark blue, battalion colours (light blue, yellow, brown and white);
12th Australian Brigade (4th Australian Division) circle lower half dark Blue; battalion colours (upper half) same as 4th Brigade;
8th Australian Brigade (5th Australian Division) a vertical rectangular patch divided vertically rear half yellow (brigade), battalion colours (front half) black, purple, brown and white.
Cheers
Chris